Rock drilling device



Oct. 10, 1933. E. G. GARTIN ROCK DRILLING DEVICE Original Filed Dec. 30,1927 fiwenZ'ar: EJ277267 6?. Garh'ru f/M ,4- mmm.

Patented Oct. 10, 1933 noon DRILLING DEVICE 1. Elmer G. Gartin,ClaremontfN/H assignor to Sullivan Machinery Company, a corporation ofMassachusetts Application December 30; i927, Serial No. 243,727

' Renewed February 11, 1 932 I I My invention relates to rock drillingdevices and more particularly to fluid pressure operated percussivemotors of thehammer drill type.

- An object of my inventionis to provide an im 3 proved pressure fluid.operated motor. I Another object of my invention is to provide animproved pressure fluid operated hammer drill of the valved type. Afurther object of my invention is to provide an improved drilling motorhaving an improved valve mechanism. A still further; object of myinvention is to provide an improved drill-' ing motor having a coaxialrelation of the distributing valve and rotation mechanism by means ofwhich fluid distribution. will be -im proved. Yet another object is toprovide an improved pressure fluid motor having an improved valvemechanism of the compression-actuated 30 I The illustrative embodimentof the invention comprises a cylinder member 1; having a bore 2 in Iwhich a hammer piston- 3- is reciprocable. The piston 3 is provided.with a forwardly extending striking portion 4 having a splinedconnection with a nut 5 secured-in the rear end of a chuck member 5which also carries a bushing 7 in which a hollow rock drill steel 8 issupported for the hammering action of the hammerpiston. The front-end ofthe cylinder is closedby abuffer blocku9 which is-;secured between thecylinder member 1 and the chuck. housing member is in any suitablemanner as-,- for example, bysiderods one of. which is shown at 1.1.Therear end of the cylinder bore 2 is closed byia member 12 which is hasa -rca rwardly extending sleeve 14 formed integral therewith. To therearof the bore 2 the cylinder member. 1 is provided with. an enlarged bore16 which receives the member 12; the mamher" 1.7,. constituting a valvechest, the ratchet mechanism 18,- and; a forwardlyprojecting reducedportion .19 upon a rear'head'member 20; A.e1eansi'ng'fluid supply tube21 is supported in a suitable manner in the rear head member. 20 andextends through. the. various ipartsi of the drilliinto the Caltraversed by longitudinal passages 13 and which rear end of the hollowdrill steel 8. A throttle valve 22 is rotatably mounted in the reargheadmember 20 and controls the supply of motive fluid from achamber23therein through a port'24 to a passage 25-which extendsforwardly through the 0. head member 20, through the ring 18 supportingthe ratchet mechanism and through the valve 7 chest member 17. A riflebar 26-carrying at; its

rear end apawl carrier 27 whose pawls engage with ratchet teeth 28 isrotatably mounted within 5.

the sleeve 14', and has a relatively long, smooth,-

cylindrical portion extending substantially throughout the full lengthofthe sleeve andhas a spirally rifled forward portion-29 cooperatingwith the ride nut 30 carried within the rear endof the 7 0. piston. Thehollow chest member 17 is provided with a bore. generally designated 32and comprising a rear portion of smaller diameter 33 and a forwardportion of larger diameter 34. I The inner wall 015 the chamber isformed by the periphery of the sleeve M The extreme rear end of thebore-33 isconnected by 'a passage 35 with the fluid supply passage 25.Spaced ,forwardlyfromthe pas-. sage 35 is an exhaust groove36-communicating by a passage 37 with the atmosphere. Still furthe'rforwardr a peripheral groove 38 communicates. with the smaller bore .32-and. is connected by a passage 39 with the bore2 of the cylinder at'apoint 40 adjacent the forward end ofthe cylinder. Aport '41 communicateswith the smaller bore' 32 at a point near the-forward end-there ofserving toconnect thebore with the fluid sup-' ply passage 25. A passage43'communicates near the front endrof the larger bore 34; with thelatter 9o the bores.33 and 34 serves to facilitate. the fluid supply,this passage being connected; by a' groove 16 with the passage 25. Avalve member 47 is provided arranged concentrically with the sleeve 14-and rifle bar 26- and having a larger head'or spool 48 .reciprocable inthe larger bore 34 and a reduced sleeve-like portion. 49 reciprocable inthe reduced bo're33. This sleeve-like portion The abutment 52 permitsfluid passing to the passage 35 to act upon the greater portion of thesmaller end of the valve. A further passage 54 extends from a point atapproximately the rear end of the larger bore 34 in the valve chest to aport 55through thewall of the cylinder 2. .Co mv munication betweenthe'passage 54 and the larger bore 34 of the valve chest cannot becompletely closed by the valve portion 48. A vent port 56 extends from aspaced point in the larger bore 34 to the atmosphere. The cylinder 1 isprovided with exhaust port means 57 in a position to be overrun by thepiston head nearthe endv ofits stroke in each directioni vThe mode ofoperation of the mechanism described is self-evident. Assuming that theparts are initially in the position'shown in Fig. L'fluid supply throughthe valve 23 will passby way of the passage '25 and the corresponding.passage 44 through the passages 35 and 43 and the valve willremain inthe position shown since the area at'the forward 'end "of the largerportion of the valve will exceed that subjected to the pressure throughthe passage 35; The'fluid will accordingly flowthrough th'e'ports' 43and 13 into the rear end of the bore of the cylinder and act upon therear end of the pistomforcing the latter forward. Atthis time the frontend of the-cylin-' 'der bore is exhausted to atmospherethrough port 40,passage '39. through the bore -33,=past the groove in the valve,"throughtheannular groove 36 and thence through the lateral port 37 to ainosphere. When the'pis ton 3 reaches a position in which the port isuncovered, pressure fluid flows from the rear endfiof' the cylinder.bore through the passage 54 filling thespace in the bore 34 to therearof thelarger portion or spool 48 of the valve 47 and as the pressure isflowing rapidly through the ports 43 and Bit is substan tially lowerthanthe c'ombined pressures acting on the rear areas of the spool 48 andsleeve-like portion 49. Therefore as the pressure acting on rear areasof the valve is materiallygreater than the pressure acting on thefront'areaof the; valve, "the latterwill be thrown from f theposition-shownin Fig. l to the position shown in FigY-Z'. Itwill benoted that when the valve 4'! is thrown into the position shown in Fig.2 the enlarged portion or spool 48 enters the forward portion 'of thebore 34 th'erebycutting ofi. communication between the ports 43 andthe'ports 13. Upon further forward movement of the piston'3the exhaustport 57 is opened therebyconnesting the rear 'end of the cylinder borewith the atmosphere." 1

Itwill further be noted that when the valve is in the position shown inFig.2 pressure fluid flows from'thesupply passages 25, 44 throughthe'lateral ports '41, throughthe bore 33, past the groove 50 in the"valve, and thence through the passage 3 9 and' port 40 to the forwardend of the cylinder bore wherein the fluid acts upon the forward end ofthe piston forcing the latter'rearwardly. At this time the rear end ofthe cyl-,

inder'bore is exhausted to'atm'osphere through the exhaust port 57 whilethepressure within the stant pressure acting on the rearward area of thesleeve-like portion 49 of the valve. The valve 4'7 is then thrownrearwardly by compression from the position shown in Fig. 2 to theposition shown in Fig. l, the forward end of the cylinder bore againbeing connected with the fluid supply while the rearend of thecylinder'boreis exhausted to atmosphere. The above cycle of events isrepeated throughout the normal operation of the motor.

As a result of this invention an improved pressure fluid motor isprovided wherein the power and efliciency of the motor is materiallyincreased. It will further be noted'that by arranging the distributionvalve concentrically with the rotation mechanism the fluid distributionhas been materially improved, it being possible by more, by arrangingthe valve in the rear of and in axial alinement'with the motor cylinderit has been made possible to throw the valve in one directifin directlyby'compression built up in the rear end of the cylinder bore by thehammer piston. These. andother advantages of the improved motor will beclearly apparent to those skilled in thisart.

'While I have in this application specifically described one formwhichmy invention may a. sumein practice, it will be understood that thisform'of the same is shownfor purposes of illustration and that theinvention may be modified and embodied in various otherforms withoutdeparting from its spirit or the scope of the appended claims. I What Iclaim as new and desire to secure by Letters Patent-is:

1.-In a pressure fluid motor, a cylinder,

piston 'reciprocable therein,- and fluid distribution means forsupplying fluid to and exhausting fluid from said 'cylinderto effectreciprocation of saidpiston including a valve chest having a bore, afluid supply passage communicating with oneend of said bore, an exhaustpassage-com municating with said bore, a fluid conducting passagecommunicating with said bore at a point between the supply and exhaustpas sages forsupplyingfluid to the front end of 'the motor cylinder, apassage communicating with the valve chest bore between said fluidconducting passage and said supply passage and communicating withthe'cylinder, a valve reciprocably mounted in the valve chest bore forcontrolling said supply; exhaust and fluid conducting passages, andpassage means for supplying fluid to the rear end of the cylinder andalso controlled by said valve. 1 V 1 V r? 2. In a pressure fluid motor,'a cylinder, 9. piston -reciprocable therein, and fluid distribu-' tionmeans for supplying fluid to and exhausting fluid from said cylinder toeffect reciprocation of said piston including: a valve chest having abore, a fluid supply passage communicating with one end of. said bore,an exhaust passage communicatingwith said bore, a fluid conductingpassage communicating with said bore at a point between the supply andexhaust passages for supplying fluid to the front end of the. motorcylinder, a passage communicatingwith the valve chest bore between saidfluid conducting passage and said supply passage and communicating withthe cylinder, a valve reciprocably mounted in the valve chest bore forcontrolling said supply, exhaust and fluid conducting passages, a ventpassagecontroiled by said valve for connecting said last mentionedpassage to atmosphere, and passage means for supplying fluid to the rearend of the cylinder and also controlled by said valve.

3. In a pressure fluid *motor, a cylinder, a piston reciprocable'therein, and fluid distribution means for supplying fluid to andexhausting fluid from said cylinder to effect reciprocation of saidpiston including a valve chest having a bore, a fluid supply passagecommunicating with one end of said bore, an exhaust passagecommunicating with said bore, a fluid conducting passage communicatingwith the bore at a point a between the and exhaust passages forsupplying fluid to the front end of the motor cylinder, an additionalsupply passage communicating with the bore at a point between said lastmentioned passage and said flst mentioned supply passage, a valvereciprocably mounted in the valve chest bore for controlling saidpassages, and

passage means for supplying fluid to the rear end tional supply passagecommunicating with the bore at a point between'said last mentionedpassage and said first mentioned supply passage, a passage communicatingWiththe valve chest bore between said supply passages and communicatingwith the cylinder, a valve reciprocably nio'unted in the valve chestbore for controlling said supply, ez-rhaust and fluid conductingpassages, and passage means for supplying fluid to the rear end or thecylinder and-also controlled by said valve.

5. In a pressure fluid motor, a cylinder, a piston reciprocable'therein, and fluid distribution means for supplying fluid to andexhausting fluid from said cylinder to effect reciprocation of saidpiston including a valve chest having a bore, a fluid supply passagecommunicating with bore, an exhaust passage communicating 'Wiil'l saidbore, a fluid conductingpassage communicating with the bore at a pointbetween the supply and exhaust passages for supplying fluid to the frontend of the motor cylinder, an additional supply passage communicatingwith the bore at a point between said last mentioned passage and saidflrst mentioned supply'passage, a passage communicating with the 'valvechest bore between said supply passages and communicating with thecylinder, a valve reciprocably mounted in the valve chest bore forcontrolling said supply, exhaust and fluid conducting passages, a ventpassage controlled by the valve for connecting said last mentionedpassage with thev atmosphere, and passage means for supplying fluid fromsaid cylinder to effect reciprocation of said piston including a valvechest having a differential bore, passages communicating with thevalve'chest'bore comprising an exhaust passage, a passage ,forconducting pressure fluidto the front end of the cylinder, a thirdpassage leading to the cylinder, for conducting pressure fluid from thecylinder to a pressure area on the valve to throw the latter, a fluidsupply passage communicating with the valve chest bore at a pointbetween said last mentioned passage and saidsecond mentioned passage,and a differential valve in said valvechest bore for controlling saidexhaust, fluid conducting and supply passages.

7. in a pressure fluid motor, a cylinder; a piston reciprccahle therein,fluid distribution for supplying fluid to and eizliaustingfluid fromcylinder toeflect recprocation of said'piston including a valve chestheving a diiierential bore, communicating with the valvechest borecomprising an exhaust passage, a passage iorconducting pre sure fluidtdthe front end or the cylinder, a third passage leading to the cylinderfor conducting pressure fluid from the cylinder to pressureareaon valveto throw the latter, fluid supply passage communicating with the valve hseat a point between said last mentioned and second mentioned passe, adifle .Ltial valve insaid valve chest bore exhaust,fluid conducting andsupply passages, and a passage controlled bythe valve for venting saidthird passage to atmosphere. :3. In a pressure fluid motona cylinder, 2.piston procaole therein. and fluid distribut on means for supplyingfluid to and exhausting fluid from said cylinder to effect reciprocationof said piston including a valve chest having a differential bore, passaes cornn- "nicating with the valve chest h re comprising an exhaustpassage, a passage for condue pressure fluid to the front end of thecylinder, a third. passage leading to the cylinder for conductingpressure fluid from the cylinder to a pressure area on the valve tothrow the latter, a fluid supply passage communicating with the valvechest bore at a point between, said last mentioned passage and saidsecond mentioned. passage, a differential valve in said valve chest borefor controlling said exhaust, fluid conducting and apply a passagecontrolled by the .valve for venting said third mentioned passage toatmosphere, and passage means also controlledby said valve for supplyingpressure fluid to the rear end of the cylinder. I,

9. In a pressure fluid motor, a cylinder, a piston reciprocable therein,and fluid distribution means for supplying fluid to and exhausting fluidfromi like body portion fitting the smaller bore and an enlarged endspool fitting the larger bore,'said sleeve-li ortion having a peripheralgroove between its ends, a supply passage communicating y 'with thelarger bore, and three passages communicating with the smaller bore, oneleading to I the cylinder, the second to the fluid supply,'and' thethirdto exhaust, the groove in the sleeve-like portion of said valve,upon reciprocation of. the

valve, connecting alternatively the passage lead ing to the cylinderwith the supply and exhaust passages.

V 10. In a pressure fluid motor, a cylinder, a pis ton reciprocabletherein, and fluid distribution means for supplying fluid to andexhausting fluid from said cylinder to effect reciprocation of saidpiston including a valve chest having adifierential bore, a diflerentialvalve reciprocably mounted in the valve chest bore and havinganelongated sleeve-like body portion fitting the smaller bore and anenlarged end spool fitting the larger bore, said sleeve-like portionhaving a peripheral groove between its ends, a supply passagecommunicating with the larger bore, another supply passage communicatingwith the smaller bore, two other passages communicating with the smallerbore and a third with the larger bore, two of said last mentionedpassages leading vto the cylinder and the third to exhaust, the groovein the sleeve-like portion of said valve, upon reciprocation of thevalve, connecting alternatively one of the passages leading to thecylinder with the second mentioned supply and the exhaust passages, anda vent passage controlled by said valve and communicating with thelarger bore for connecting said other passage leading to the cylinder toatmosphere.

ll. In a pressure fluid motor, a cylinder, a piston reciprocabletherein, and fluid distribution means for supplying fluid to andexhausting fluid from said cylinder to effect reciprocation of saidpiston including a valve chest having a difieren tial bore, adiflerential valve reciprocably mounted in the valve chest bore andhaving an elongated sleeve-like body portion fitting the smaller boreand an enlarged end spool fitting the larger bore, said sleeve-likeportion having a peripheral groove between its ends, a supply passagecommunicat ing with the larger bore, another supply passagecommunicating with the smaller bore, two other passages communicatingwith the smaller bore and a third with the larger bore, two of said lastmentioned passages leading to the cylinder and the third to exhaust, thegroove in the sleeve-like portion of said valve, upon reciprocation ofthe valve, connecting alternatively one of the passages leading to thecylinderiwith the second mentioned supply and the exhaust passages, avent passage controlled by said valve and communicating with the largerbore for connecting said other passage leading to the cylinder toatmosphere, and a passage also controlled by the valve for connectingthe larger bore with the rear end of the cylinder.

12. In a pressure fluid motor, a cylinder, a piston reciprocabletherein, and fluid distribution means for supplying fluid to andexhausting fluid from said cylinder to effect reciprocation of saidpiston including a valve chest having a differential bore, adifferential valve reciprocably mounted in the valve chest bore andhaving an elongated sleeve-like body portion fitting the smaller boreand an enlarged end spool fitting the larger bore, said sleeve-likeportion having a pheripheral groove between its ends, a supply passagecommunicating with the larger bore, two passages communicating with thesmaller bore and a third with the larger bore, two. of said lastmentioned passages leading to the cylinder and the third to exhaust,another supply passage leading to the smaller bore, the groove in thesleeve-like portion of said valve, upon reciprocation oi the valve,connecting alternatively one of the passages leading to the cylinderwith the last mentioned supply and the exhaust passages, a vent passageconmeans for supplying fluid to and exhausting fluid from said'cylinderto eflect reciprocation of said piston including a valve chest having adifferential bore having closed ends, a differential valve reciprocablymounted in the valve chest bore and having a sleeve-like body portionfitting the smaller bore and an enlarged end spool fitting the largerbore, a passage for supplying fluid constantly to one end of the smallerbore to act on one end of the sleeve-like body portion of the valve,three passages communicating with the smaller bore, one an exhaustpassage, another a fluidsupply passage, and the third a passagecommunicating with the smaller bore between said exhaust and fluidsupply passages and leading to the forward end of the cylinder, twopassages communicating with the larger bore, one a supply passage andthe other leading to the cylinder, fluid flow through said passagesbeing controlled by said valve and a third passage communicating withthe larger bore and leading to the cylinder.

14. In a pressure fluid motor, a cylinder, a piston reciprocabletherein, and fluid distribution means for supplying fluid to andexhausting fluid from said cylinder to eflect reciprocation of saidpiston including a valve chest having a differential bore having closedends, a differential valve reciprocably mounted in the valve chest boreand having a sleeve-like body portion fitting the smaller bore and anenlarged end spool fitting the larger bore, a passage for supplyingfluid constantly to one end of the smaller bole to act on one end of thesleeve-like body portion of the valve, three passages communicating withthe smaller bore, one an exhaust-passage, another a fluid supplypassage, and the third a passage communicating with the smaller borebetween said exhaustand fluid supply passages and leading to the forwardend of the cylinder, two passages communicating with the larger bore,one a supply passage and the other leading to the cylinder, fluid flowthrough said passages being controlled by said valve, a third passagecommunicating with the larger bore and leading to the cylinder, apassage communicating with the larger bore for venting one of thepassages leading to the cylinder to atmosphere and also controlled bythe valve. 7

15. In a pressure fluid motor, a cylinder, a piston reciprocabletherein, and fluid distribution means for supplying pressure fluid toand exhausting fluid from said cylinder to efiect reciprocation of saidpistonincluding a valve chest having a differential bore, a differentialhollow sleeve valve reciprocably mounted in the valve chest bore andhaving an enlarged flange fitting the larger bore and an elongatedimperiorate sleeve-like body portion fitting the smaller here, saidvalve having pressure areas the action upon each of which of pressurefluid produces a pressure acting longitudinally of said valve, saidpressure areas all being formed either upon an end or upon the outsideof said valve, passages for conducting pressure fluid to said areas forpositioning said valve including a passage communicating with the largerbore at the rear side of said flangefor conducting pressure fluid from"the motor cylinder-to the rear pressure area on said flange to throwsaid valve forwardly, a fluid conducting passage communicating with saidvalve chest bore and leading to the forward'end oiithe motorcylinder; anexhaust passage communicating with said valve chest .bore,a fluid supplycommunicating with said valve chest is nd fluid conducting passage com-.mun to the rear end of themotor cylinder, said valve controlling thesupply or pressure fluid through ffluid :conducting 'passages to theopposite said exhaust passage from the forward'end of said motorcylinder, and valve being thrown into its rearward position bycompression pres' sure built up in the rear end of the cylinder,

during the rearward piston stroke and acting on the forward pressurearea on the forward end of valve.

id l'na pressure fluid motor, a cylinder, a. piston reciproca'oletherein, fluid distribu-' tion means for supplying pressure fluid to andexhausting fluid from said cylinder to effect re ciprocation of saidpiston including a valve chest having a diflerential bore, adifferential hollow sleeve valve reciprocably mounted in the valve chestbore and having an enlarged flange fitting the larger bore and anelongated imperforate sleeve-like body portion fitting the smaller bore,said valve having pressure areas, passages for conducting pressure fluidto said areas for positioning valve including a passage communieatingwith the larger bore at the rear side of leading to the forward end or"the motor cylinder,

an 'Anaust passage communicating with said val e chest bore, a fluidsupply passage communi eating with said valve chest bore, and a fluidconducting passage communi ating with said valve chest bore and leadingto the real-lend of the motor cylinder, said valve controlling thesupply of pressure fluid through said fluid conducting to, the oppositeends of said motor cylinder and the exhaust from the forward end of saidmotor cylinder, and said valve beingv thrown into its rearward positionby compression pressure built up in the rear end 01' the cylinder duringthe rearward piston stroke and acting on the forward pressure area onthe for- V ward end oi said valve.

17. In a pressure fluid motor, a cylinder, a piston reclprocabletherein, and fluid distribution' ing pressure areas, passages forconducting pres-' sure fluid to said areas for positioning said valveincluding a passage communicating with the larger bore at the rear sideof said flange for conducting the pressure fluid from the motor in withsaid valve chest bore and leading cylinder to the rearipre'ssure areaonsaid. flange tot'nrow said-valve forwardly, a fluid conductingv passagecommunicating with said valve chest bore and leading to the forward endof the motor.-

ducting passages to the opposite ends or" said 7 motor cylinderandthe'exhaust from theforward ends of said motor cylinder andenhaustthrough end or" said mot-or cylinder, and said valvebeing thrown intoits rearward position by compression pressure built up in the rear endof the cylinder during the rearward-piston stroke and acting on theforward pressure area on the forward end of saidvalve, and a ventpassage communicating with the larger bore and controlled bysaid valveflange for venting the larger here at the rear side or" said flange-toatmosphere;

13. In a pressure fluid motor,- a cylinder, a

piston reciprocable therein, and fluid distribution means for supplyingpressure fluid to and exhausting fluid from said cylinder to effect recirocation of said piston including a valve chest having a differentialbore, a differential hollow sleeve ivalvereciprocably mounted in thevalve chest bore and having an enlarged flange fitting the larger boreand an elongated imper iorate sleeve-like body portion fitting thesmaller bore, said valve having pressure areas the action upon each ofwhich of pressure fluid produces a pressure acting longitudinally ofsaid valve, pas

sages for conducting pressure fluid to said areas for positioning saidvalve including a passage communicating with the larger bore at the.rear sideof said flange for conducting pressure fluid from the motorcylinderito the rear pressure area on said flange to throw said valveforwardly Jand' a passage constantly supplied with live pressure duringrunning of said motor-and communicating with said valve chest bore at apoint in the latter spaced from and further to the rear than the pointof communication of said last mentioned passage, to provide a forwardbias to said valve, a fluid conducting passage communicating with saidvalve chest bore and leading to the forward end of the motor cylinder,an exhaust passage communicating with said valve chest bore, afluidsupply passage communicating with said valve chest bore, and afluid conducting passage communicating with said valve chest boreandleading to the rear end of the motor cylinder, said valve controllingthe supply of pressure fluid through said fluid conducting passages to.the

opposite ends of said motor cylinder and exhaust through said exhaustpassage from the forward end of said motor cylinder, and said valvebeing thrown intoiits rearward position by compression said motorincluding a valve chest in longitudinal alinement with said cylinder, atubular valve reciprocable longitudinally in said valve chest andcomprising an imperforate sleeve open from end .to end, said valvehaving an area in constant communication with the rear end of thecylinder whereby the valve is thrown in the rearward direction bycompression pressure'built up in the rear end of the cylinder on thereturn stroke of the piston, means for throwing the valve in theopposite direction comprising an annular shoulder on said valvepresenting a rearwardly facing area, means for subjecting the latterarea to intermittent pressure, and means for subjecting a ferentialvalve said valve chest and comprising an imperforate sleeve open fromend to end, said valve having aniarea in constant communication. withtherear end of the cylinder whereby the valve may be thrown rearwardlyby compression of the fluid which is trapped in the rear end of thecylinder at the time of closing of the exhaust, and means forthrowingthe valve in the opposite direction including a rearwardlyfacing area adapted to be subjected to intermittent pressure and an areadisposed rearwardly of the latter area; and subjected to constant fluidpressure.

. v a ELMER G. GARTIN.

